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Back in December, a 44-foot sei whale (Balaenoptera borealis) washed ashore and died on the Galveston coastline near the Terramar subdivision. It was sighted by a passerby who spied it rolling in the waves, its spout the only clear sign that it was alive. A crowd gathered, including a local dolphin rescue group and machinery crews who brought out a front-end loader.

Not much could be done for the whale, unfortunately, since its size prevented advocacy groups and interested citizens from helping it back into the ocean. A frightened whale, rolling in the waves, poses a serious threat of crushing those who wish to help it. Onlookers had no choice but to watch and hope for the best.

Sei whale (Balaenoptera borealis)

When the whale stopped spouting, a sign it was no longer breathing, crews dragged it ashore so a necropsy, or animal autopsy, could be performed and its species could be identified. After the seven-hour procedure to determine its cause of death, results were inconclusive and remained murky for several weeks. A number of combined factors could have contributed to its becoming stranded. The whale was dragged on shore by front-end loaders and buried in a deep trench near the water table, common practice for any beached cetacean.

“Typically when dolphins are beached, we take them to an off-site location and bury them. This whale was 60,000 pounds, so we buried it at the site where it washed up,” said Mary Beth Bassett, Public Relations Coordinator for the Galveston Island Convention and Visitors Bureau.

Woodcut of Dutch whalers in the 1800s.

The World Wildlife Fund lists the sei whale as an endangered species, with less than 12,000 individuals estimated to live in today’s oceans. Commercial whalers targeted the species and hunted them heavily when blue and fin whales became scarce, driving their numbers dangerously low. While advocacy groups continue to work to restore the population, the sei whale, and ocean-going whales in general, remain difficult to track and understand, and so must be protected through international whaling laws.

Because whales use echolocation to navigate, sonar from commercial ships might confuse whales, driving them into dangerous situations that lead to beachings, explained Tina Petway, Houston Museum of Natural Science Associate Curator of Malacology. This could have played a factor in the death of this whale, which was also probably ill and its navigational faculties already impaired.

Fin whale (Balaenoptera physalus)

“Whales frequently have parasites that get in the inner ear and cause them to have echolocation problems and lose their balance easily,” Petway said. “They can be led off their paths when their echolocation doesn’t seem to work.”

Petway theorized that some of these ocean-going whales unused to inshore areas can become “lost” between sandbars. When led astray, they might pass a sandbar and believe they are heading back out to sea when in fact, they are in a trough between sandbars. By this time, they are trapped and the inshore current continues to push them further onto the beach.

Bryce’s whale, (Balaenopterabrydei)with three distinctive ridges on its head.

“But something was wrong before it got stranded,” Petway said.

The sei whale belongs to a family of fin whales characterized by a small, backward-curving dorsal fin far down their backs. Only four whales have this specific characteristic, the blue whale, the fin whale (its name no surprise), the Bryde’s (pronounced broo-des) whale, and the sei whale. The Bryde’s and the sei are difficult to distinguish from one another. They are almost identical in size and shape, but the Bryde’s has three ridges on the top of its head running from its blowhole to its snout, while the sei whale has only one.

“Almost all species of whales can be found in the Gulf of Mexico,” Petway said. “We have pods of killer whales (orcas) in the Gulf of Mexico. They don’t travel. They are resident pods.”

Fin whales all use baleen to catch and filter krill out of large gulps of seawater. They swim through large schools of krill, or copopods, with their mouths open, and push the water through the baleen (which has the appearance of broom bristles hanging from the top of the mouth) with their tongues. Like dust, the baleen catches the krill, which the whale then swallows.

The growing amount of bits of plastic in the ocean, now so far broken down some of it is microscopic, is a concern for baleen whales. Because the bits of plastic are about the same size as krill, they are filtered out and swallowed with all the rest. Scientists are unsure how this affects whales since they are difficult to study, but it can’t be good. You can help these whales when you observe World Oceans Day June 8 this year by making a pledge to reduce your plastic use and begin recycling. Spread the word and encourage others to do the same. Plastic in the oceans is a serious world emergency. Whales like the sei and other fin whales, which are already endangered, need no more problems threatening their numbers, and plastic affects the entire food chain, including we humans, who also depend on the oceans as a source of food.

You can size yourself up to a complete whale skeleton in HMNS’s newest exhibit, Cabinet of Curiosities, opening Friday, May 6. Personnel are currently restoring the skeleton, which has been in storage for a number of years, and will hang it from the ceiling as part of this hands-on history of wonder.

This post was written by Diana Birney, Supervising Marine Biologist for our upcoming SHARK!exhibit, opening August 29, 2015.

We fear them, we love them, and we are fascinated by them. We have a whole week on television dedicated to them that draws millions of viewers every year. Humans have an amazing obsession with this interesting group of animals, especially considering that we really don’t know that much about them.

It’s clear from the popularity of movies like Jaws and Sharknado that we love to be scared by sharks. While there is a good reason to give sharks their space, they are not the crazed “man-eaters” that Hollywood has often portrayed. In fact, since 1911 there have only been two deaths and less than fifty unprovoked attacks by sharks in Texas.

You’re actually more likely to be struck by lightning than you are to be attacked by a shark.

However, every time you enter a body of water, you should go in with the knowledge that a shark could potentially be there. When it comes down to it, it’s their space — not ours.

That doesn’t mean that you can never go in the water again, it just means be smart about what you do in the ocean…

So go to the beach, bring your sunscreen (and reapply it often!). But also bring your knowledge of what lives in the habitat you are about frolic in. Feel like you don’t know enough? Don’t worry! Here’s a nice set of guidelines for your next trip:

1. Sharks aren’t searching for humans to eat

There is no evidence to suggest that sharks like eating people. In fact, considering the numbers of people that go to the beach and the attack statistics, it would seem that sharks DON’T like eating people. A beach is a potential buffet at certain times of the year, but the sharks don’t seem to take advantage of it (good news for us!).

When people do get bitten, it’s usually one bite and the shark lets go. This is similar to the other night when I had a plate of broccoli I was going to town on and ran into a bite of mushroom (I hate mushrooms). I promptly spit that nasty bite out and went back to my broccoli feast (YUM). Sharks tend to follow schools of fish or, for our larger shark friends, mammals such as seals. Schools tend to frequent coast lines and often when someone is bitten there is a school of fish in the area that the shark was intending to chow down on.

2. Sharks have AMAZING noses

Sharks can sense blood in a ratio of one part per million. They also have sensors on their noses called ampullae of Lorenzini. These are electroreceptors that can sense the electrical field given off by everything swimming around in the ocean — including you and me! If a wounded person or animal enters the water, a shark can be drawn to the blood but also to the electrolytes that pour out of the wound as well.

There is a common idea that punching a shark on the nose will make it less likely to attack you. This stems from the fact that the ampullae are all over the nose and punching the shark might disrupt the electroreceptors. Another reason this (sometimes) works is that most sharks like certain prey items and most of those prey items don’t know how to punch — giving the shark a strong clue that it won’t like eating you.

However, it’s important to not just go around punching sharks… right under their nose is a huge mouth with lots of teeth, and you may end up just losing an arm instead of scaring the sharks.

3. “There’s a chance I’ll bite if you bother me too long” – sharks

This summer there was a shark bite incident off of the coast of California with a White Shark. A swimmer got too close to a fishing line that caught a shark. The shark had been on the line long enough to be mad at everyone and everything. When the swimmer approached it, unaware it was even there, the shark lashed out. The moral of the story is that sharks, like dogs and cats, have no way to communicate with us that they are uncomfortable or in pain. The only avenue available is their teeth. Many bites are exploratory or just to say “BACK OFF.”

A good rule of thumb in any environment is that if it has teeth it can/will bite.

4) Stay with your swimming buddy

Having a buddy is essential for beach safety. Rip tides can pull even proficient swimmers down and out into the ocean (and are actually much more likely to happen to you than a shark attack). Sharks, just like other apex predators, e.g., lions, tend to go after prey that is separated from the pack — it makes for an easy dinner. So if you are swimming alone a shark might think you are a solitary prey item. If you are with someone else, the shark might still think you are prey, but will be less likely to attack a small “pack” rather than a solitary animal.

The buddy system is also beneficial just in case something does happen. Your buddy can get help and report exactly what happened in case you are in shock or missing.

5) Daytime is the best playtime

Most sharks hunt at night, dawn and dusk when they can see the best. Fortunately, most people go to the beach during the day. Just be extra careful if you are going out in the evening or at night because the shark can see you better than you can see them, guaranteed. However, if you are in an area frequented by White Sharks remember that they tend to hunt during the day when their traditional prey are more active.

6) Play smart

It’s important to know what signs indicate a higher chance of sharks in the area. Sandbars and the drop offs around sand bars are a common shark hang out. Sharks can swim in extremely shallow water, so don’t let the low water level lull you into a false sense of security.

An easy sign of sharks to watch out for is the presence of other animals. I know it’s hard to stay back when you see a bunch of fish in the water (as a Marine Biologist, I can be guilty of not staying away from schooling fish), but sharks enjoy snacking on large groups of fish. We wouldn’t want you to end up a morsel in the shark’s buffet.

However, we can’t always see schooling fish. Don’t worry too much since there are more obvious signs you can watch out for including: birds, dolphins/porpoises and lots of splashing. Birds will attack schools from the air, so if you see many birds diving in a particular spot, you can safely assume there are fish there and will want to stay away from that location. Same with dolphins and porpoises. They eat a lot of the same foods that sharks eat, so do not assume there are no sharks just because you see dolphins. Splashing is also a key sign to sharks that prey is in the area since schools of fish tend to ascend and splash around near the surface. So, again, stay away from areas that show signs of splashing, and it’s also a good idea to keep your splashing around to a minimum.

7) Know your local sharks

It’s also good to know your local sharks. The Gulf of Mexico is home to many different species, some sharks you might not see — much less have to worry about. Others, like the Bull shark account for all of the Texas deaths from sharks (don’t be too alarmed, again, there have only been 2 since 1911). We also have thresher (my personal favorite shark), nurse, blacktip, tiger, many different hammerhead species, and many more.

If you followed the news this summer, you might have seen a White Shark named Katherine approaching Texas. Katherine shows us that we can get Great White Sharks in the Gulf. For more information on Katherine and many other tagged sharks you can go to OCEARCH.org. If you are travelling and plan on going to the water, it’s helpful to know what sharks are in the area and how likely your are to see them.

In the long run, it’s important to remember that shark interactions are NOT common, you just want to be prepared and armed with knowledge whenever you hit the beach.

Life first evolved about 3.5 billion years ago, at the beginning of the Precambrian Eras. At first, life was made up of simple microbes (bacteria) that could survive horrible conditions, including acid oceans and no oxygen in the air or water.

For 2.7 billion years, the sea bottom remained (mostly) peaceful, quiet and flat. Microbes built wide mats that sealed the mud surface, stabilizing the sediment. Advanced microbes like blue-green algae began pumping oxygen into the atmosphere and ocean. The microbes had few enemies — no big, energetic animals disturbed the bottom. Day after day, week after week, year after year, bits of sediment kept falling down through the ocean water. The clay and silt continued to make layer after layer of sediment, and the ecosystem was stubbornly two-dimensional — all life lived on the surface or the bottom. The subsurface was empty.

Then, around 700 million years ago, the Vendian Period began. A few life forms like Charnia and its kin got up to a half a foot tall, acquiring the shape of bloated feather plumes. Still, no one was churning up the mud or otherwise disturbing the microbial mats.

Life in the Pre-Cambrian still was lovely, idyllic and BORING!

Today’s oceans teem with life forms that burrow through the bottom mud and live in cleverly constructed holes. Thousands of creatures, large and small, plow through the sediment looking for food. Plowers and burrowers include snails and bristle worms, long-necked clams and sea-cucumbers, plus a bewildering variety of groups without common names. The Precambrian world was totally devoid of all this action.

Finally and suddenly 540 million years ago, the Precambrian peace was broken. The Vendian Period ended when the microbial mats were attacked and ripped apart. Holes were excavated down into the mud. Bottom sediment was churned up. The long reign of the soft, quiet, two-dimensional world at last was terminated.

The Cambrian Explosion had begun.

From this moment on, the rules of life were changed, and the ecosystem went into 3D. Dozens of new species evolved to take advantage of living deep in the mud. Other species hunted the species in the mud. Still more species swam above the surface looking for prey hiding below. Trilobites appeared and flourished. Fishy-things evolved.

Who destroyed the Precambrian mats? Who released the potential of evolution? Where do we send the thank-you note?

The fossil burrows are clues. At the end of the Vendian and the beginning of the Cambrian Period, U-shaped burrows appear all over the globe wherever shallow seas existed. Something was diving down through the mats and coming back up, again and again. This was the burrower who was destroying the ancient system of mats.

There are suspects alive today that make U-shaped burrows quite like the ones that ripped apart the Vendian bottom. Usually these critters are no bigger than a small pickle. Under the microscope, these burrowers look as fierce as the man-eating worms in the movie Tremors — the beasts have stout, muscular bodies with a face that carries a scary array of hooks and barbs. When they bump into prey, the hooks snag on their victim and the whole face inverts, dragging the meal into the throat.

The cactus worm, close-up.

You can find these mini-monsters in the mud in most oceans. Technically, they are called “Priapulida,” but they have many nick-names. Our favorite is “cactus worms.” Because they have no bones or hard shells, cactus worms have almost zero chance of being fossilized unless there are very special conditions. The cactus worm would have to be buried instantly by an underwater landslide that killed the worm and sealed it under a thick blanket of sediment, keeping out any scavengers.

For the first century of paleontological explorations, up until 1909, no one could find such an avalanche bed. Then Dr. Charles Doolittle Walcott, Cambrian expert from the Smithsonian Institution, hiked up into the Canadian Rockies near Burgess Peak in British Columbia. He was looking for Cambrian trilobites, his specialty. He found what he was looking for flattened in dark slabs of clay, but there were other species, too — animals with no shell or hard parts at all.

Most exciting were the worms. Dozens of kinds of worms. Worms that ate microbes. Worms that ate trilobites. Worms that ate other worms (“Lutheran Worms”). Walcott had found the Holy Grail of Cambrian history.

But was there evidence of cactus worms? Yes!

Now we knew for certain that cactus worms had thrived in the transition from Vendian to Cambrian. We could be sure that these worms had overturned the Precambrian peace and begun the Cambrian Explosion.

They may be ugly, but remember these little creatures; they were the dynamos that restructured the oceanic world.